The present invention is directed to write driving apparatuses and methods associated with memory devices. In particular, the present invention is directed to a preamplifier apparatus for use with a differential write driver for a hard disk drive (HDD) storage device. The present invention is especially useful with a thin film inductive write driver.
The interconnecting leads between preamplifiers and read/write heads in hard disk drive devices are spaced very close together, often within a few mils of each other. The read sensors consist of very sensitive magnetoresistive material that cannot tolerate excessive voltages. In contrast, the write element consists of a thin-film inductor which requires large sub-nanosecond voltage swings for high data rate systems. Because of the close spacing of the writer and the reader, an asymmetrical voltage swing provided to the write head can couple into and damage the adjacent read element.
Manufacturers of preamplifier devices often provide their products to numerous customer-users. Each customer-user may have its own specifications for a preamplifier used in its particular end products. A manufacturer that can manufacture a single part to accommodate the demands of numerous customer-users can obtain significant economies of scale in manufacturing and other advantages by manufacturing a single multi-use part.
There is a need for an apparatus and method for use in applying write signals for driving a write head to effect writing information to a memory device that can accommodate a range of operating requirements for a variety of customer-user end products.